Process for dyeing cellulose acetate having an acetyl value of at least 59% in the presence of hydroxyalkylamine-fatty acid condensation products



United States Patent 3,233,961 PROCESS FOR DYEING CELLULUSE ACETA EHAVING AN ACETYL VALUE 9F AT LEAST 59% IN THE PRESENCE OF HYDRGXYALKYL-{AJlE/l IEglE-FATTY ACID CONDENSATION PROD- Victor S. Salviu, Charlotte,N.C., Basil S. Sprague, Berkeley Heights, N.J., and Fred Fortess,Charlotte, N11, assignors to Celanese Corporation of America, New York,N.Y., a corporation of Delaware No Drawing. Continuation of applicationSer. No. 43,285, duly 18, 1960, now mite-int No. 3,101,236, dated Aug.20, 1963, which is a division of application Ser. No. 472,758, Dec. 2,1954. This application May 15, 1963, Ser. No. 280,706

8 Claims. (Cl. 857) This application is a continuation of our copendingapplication Serial No. 43,285, filed July 18, 1960, now Patent No.3,101,236, issued August 20, 1963, which is a division of ourapplication Serial No. 472,758, filed December 2, 1954, now Patent No.2,982,597, issued May 2, 1951, and a continuation-in-part of ourapplication Serial No. 406,350 filed January 26, 1954, now abandoned.

This invention relates to the dyeing of cellulose acetate of very highacetyl value and relates more particularlyto the production of wash-fastdyed textile materials.

As is well known, the cellulose acetate textile materials customarilyemployed have acetyl values of about 53.0 to 55.5%, calculated ascombined acetic acid, and are soluble in acetone. It has been commonpractice to dye such textile materials with dispersed cellulose acetatedyestuffs to produce colored materials. However, the fastness to washingof these colored materials has not been as good as desired. Thus, forcertain purposes it is necessary to have colored materials which show afastness to washing sufficient to meet the requirements of the #3 Washfastness test of the American Association of Textile Chemists andColorists. This test involves washing a specimen of the dyed material at150 C. for 45 minutes under certain standard conditions and observingthe change, if any, in the color of the dyed material and the stainingcaused by running of the dye from said material. It has generally notbeen possible, by the use of dispersed cellulose acetate dyestuffs, tootbain dye cellulose acetate textile materials, particularly suchtextile materials dyed in full shades, capable of passing theaforementioned #3 test. In fact this #3 test is so rigorous that,generally speaking, only a very limited group of dyed materials, e.g.vat-dyed cotton regenerate-d cellulose, will pass the test. It is animportant object of this invention to produce a dyed textile materialhaving extremely good wash fastness, e.g. wash fastne'ss sumcient topass the aforesaid #3 A.A.T.C.C. wash fastness test.

A further object of this invention is to production of novel textilematerials having improved properties, such as improved wash fastness;fastness to perspiration; resistance to crocking and wet bleeding;fading and sublimation; resistance to glazing; higher safe ironingtemperatures; ability to form pleats which are permanent to laundering;increased resistance to wrinkling during washing; and decreasedshrinkage when the fabric is pressed in the presence of moist steam.

Another object of this invention is to produce a novel textile materialof cellulose triacetate or other cellulose acetate of very high acetylvalue.

Still another object of this invention is the development of an improvedprocess for dyeing cellulose acetate of very high acetyl value rapidlyand in full shades.

Other objects of this invention will be apparent from the followingdetailed description and claims.

3,233,961 Patented Feb. 8, 1966 ICC In accordance with one embodiment ofthis invention, a textile material of cellulose acetate of very highacetyl value, i.e. of 59% to 62.5% acetyl content, calculated ascombined acetic acid, is dyed at an elevated temperature in an aqueousdyebath containing a dispersed cellulose acetate dyestuif of the hightemperature, slow dyeing type in the presence of an assistant which issubstantive to the cellulose acetate of very high acetyl value, and theresulting dyed textile material is then subjected to heat treatment.

By the use of this process there are produced textile fabrics dyed infull shades, which dyed fabrics may be washed at very large number oftimes under the conditions of the #3 A.A.T.C.C. wash fastness test,without showing appreciable change in color or staining. In addition,this process results in a decided increase in the safe ironingtemperature of the textile fabric, an improvement in its resistance toglazing, and also an improvement in its resistance to mussing andwrinkling during laundering. Also, the treatment, which does notmaterially alter the hand or strength of the fabric, imparts to thefabric an ability to be permanently pleated and causes a marked decreasein the degree to which the fabric will shrink when it is pressed withmoist steam.

As stated, the dyeing of the cellulose acetate of very high acetyl valueis carried out in a heated aqueous bath of a dispersed cellulose acetatedyestuif of the high temperature, slow dyeing type. This class ofdyestuffs is well known to the art and is represented by such compoundsas 2-nitro-4-sulfonanilido diphenylamine; 4- ethoxy 2 nitrodiphenylamine,8 hydroxypropylsulfonamide; 4-nitro-2-methoxyphenyl azo4'-bis(betahydroxyethyl) amino-2'-acetylaminobenzene;4-nitro-2-methylsulfonephenyl azo4-(N-beta-hydroxy-ethyl-N-difluoroethyl) aminobenzene;4-nitro-2-chlorophenyl azo 4'-bis(beta-hydroxyet-hyl) amino 2'methylbenzene; 1 hydroxyethylamino 4 hydroxyethylamino 5hydro-xy-S-hydroxy anthraquinone; 4-nitrophenyl azo4-di-,B-hydroxyethylamino-2'-acetaminobenzeneg a mixture ofl,4-di(hydroxyethylamino)-5,8-dihydroxy anthraquinone and l-amino-4-anilido anthraquinone, 1,5dihydroxy-8-nitro-4-(metaalpha-hydroxyethyl)anilido anthraquinone; 1,8dihydroxy- 4-(para-beta-ihydroxyethyl) anilido-S-nitro anthraquinone;1-amino-4-anilido anthraquinone; and 2,4-dinitro-6-chlorophenyl azo4'-bis (hydroxyethyl) amino-2'-acetylamino-5'-methoxy benzene. Thesedyestuffs, as sold, are in the form of mixtures of a dispersing agent,such as sodium lignosulfonate or the sodium salt offormaldehydenaphthalene sulfonic acid condensation product, with theactual dye material, and usually contain about 30 to 45% of the actualdye material. Commercial dyestuffs of this type include those sold underthe names Setacyl Blue G; Eastman Blue GLF; lnterchemical Blue RLF-40(Pr. 227); Celliton Blue AF (Pr. 227); Red Y; Celliton Blue Green BA(Pr. 229); Eastone Red 2B-GLF; Amacel Red 25; Amacel Yellow CW; EastoneRed GLF; Arnacel Rubine IX (Pr. 239); Scarlet Ill (Pr. 244);Interchemi-cal Blue BGLF-40; Interchemical hie-Green BALE-40 (Pr. 229)and Amacel Violet Blue PS1. All of these dyestuffs are characterized bythe fact that when applied to the ordinary cellulose acetate textilematerials, of 53 to 55.5% acetyl value, under certain standardconditions at C., they will dye said textile materials in full shades,but when the same dyestuffs are applied to the same textile materialsunder said standard conditions at a lower temperature, i.e. 60 C., thetextile materials will be dyed only to a small extent, e.g. in shadeswhose depths are only about 65% or less of the depths of the fullshades. The standard conditions mentioned above involve a treatment of 1part by weight of the fabric in 50 parts by weight of an aqueous dyebathpersed cellulose acetate dyestuffs of the high tempera. For example,when Celliton ture slow dyeing type.

Blue AF, which is of the high temperature type, is employed as thedyestuff for both ordinary cellulose acetate and cellulose triacetate at80 C., under identical conditions, the depth of shade on the triacetateafter two hours of dyeing is only 20 or 25% of the depth of the shadeobtained on the ordinary cellulose acetate after one hour of dyeing.Some improvements can be obtained by increasing the temperature of thedyebath up to its boiling point. raised to 95 C. the depth of shade onthe cellulose triacetate is increased to 30%, as compared with the .20or 25% obtained at 80 C.

In accordance with this invention, it has been found that therate ofdyeing of cellulose .triacetate and other cellulose acetates of veryhigh acetyl value may be greatly increased by carrying out the dyeingwith the aqueous dyebath'in the presence of certain assistants which aresubstantive to said cellulose acetates. By the use of these assistantsthe cellulose acetates of very high acetyl value may be dyed in fullshades and within com mercially acceptable periods of time usingdispersed cellulose acetate dyestuffs of. the high temperature slowdyeing type. peratures well below the boiling point of the dyebath atatmospheric'pressure.

The assistants employed in accordance with this inven-' tion are, asstated, substantive to the cellulose acetate of very high acetyl value.Thus, when fibers of said cellulose acetate of very high acetyl valueare placed Thus, when the temperature of the dyebath. is.

These full shades may be attained at tern-- in an aqueous bathcontaining the assistant uniformly dispersed therein, e.g. in an aqueousbath containing 1 0.05 to 0.2% of the assistant based on the weight ofthebath and having a temperature of 65 to 90 C., the assistant isabsorbed on the fiber in a quantity which is larger, usually severaltimes larger, thanthe quantity which would be absorbed by the fiber bymere imbibition of the aqueous bath, so that the concentrationof saidassistant inthe aqueous bath is reduced. The assistant should also be agood solvent for the dyestufi and should preferably have alimitedsolubility in water. ample, one. of the preferred assistants of thisinvention, tripropyl phosphate, has a water solubility of less than 0.9%at 25 C. and about 0.5% at temperatures of 50 to 95 C., while the otherassistants are generally even less soluble.

Outstanding results have been obtained by using as the dyeing assistantssuch materials as the terpene alcohols, e.g. pine'oil, and their ethers,e.g. the terpene glycol ether known as Terposol #8, such esters astripropyl phosphate, tributyl phosphate, triamyl phosphate, trihexylphosphate, dioctyl acid phosphate, vdimethyl phthalate,

diethyl phthalate anddipropyl phthalate, 'diallyl phthal-.

ate, triallyl citrate, methyl salicylate, methyl benzoate, and theN,N-dihydroxyethyl amides of higher fatty acids, such as capric orlauric acids, which N,N-dihydroxyethyl amidesmay be prepared by reactingdiethanolamine with the higher fatty acid at an elevated temperaturewhile splitting outwater; Other materialswhich have been.

found to be effective as assistants include such aromatic compounds ascumene, biphenyl, naphthalene, tetrahydronaphthalene, trichlorobenzene,cyclohexyl phenolp o-phenyl phenol, salicylic acid, benzoic acid, themonophenyl ether of ethylene glycol, the monodichlorophenyl For ex etherof ethylene glycol, and the mono p-chlorophenyl" ether :of ethyleneglycol, the monophenyl ether ofdi tri-n-octyl phosphate, dipropyl acidphosphate, dibutyl' acid phosphate, diamyl acid phosphate, didecyl acidphosphate, dilauryl acid phosphate, dibutyl ethanolamine, diisobutylcarbitol, Maypon' K (a condensation product of a protein split offproduct and a fatty acid), Alkamine 'W30 (a fatty amine condensate),.and 'CRL 40229-G2l25, (anester' produced by condensing lauric acid and8 to 10 moles of ethylene oxide), and the aryl amine known'as Km-111.?However, thelatter mate rials are not consideredtobe as usefulgenerallyas the. previously. mentioned preferred assistants, i.e. terpenealcohols and ethers, tripropyl, triamyl, trihexyl and tributylphosphates, dimethyl, diethyl, 'diallyl and dipropyl phthalates, dioctylacid phosphate, triallyl citrate',.methyl' salicylate, :methyl benzoate,and the. fatty acid-dieth-anol amine condensation products, since in'many cases the materials are toxic; .or too highly volatile; or do notsufficiently solubilize certain of the dispersed acetate dye-v stuffs ofthe high temperature type; or have some tendency to produce spottingunlessadded dispersing agents are present; or do notincrease the tdyeingrate to the I sameextentas saidpreferred:assistants; or are at timesdeleterious to the'mechanical properties and dimensions of the fabric.

Mixtures of dyeing assistants may be employed if desired. For example,excellent results have been obtained bythe use of a mixture of tributylphosphate and the phosphate, 40% by weight :of tributyl phosphate and20% by weight of the aforementioned condensation prode net ofdiethanolamine and capric acid.

Generally speaking,the dyebath should contain a dispersing agent inorder to insure that the dye is properly? dispersed. As pointed outpreviously, the; commercially available dispersed celluloseacetate'dyestutfs are prepara tions containing such dispersing agents'inintimate mixture with the actual dye material.

of dispersing agent beyond those amounts, present in the.

commercial dyestuff. However, we have found that in the dyeing ofcellulose triacetate and othercellulo'se acetates of very'high aacetyl:value'in the presence of assistants, the presence of an excessiveamountof the dispersing agent, generally causes a decrease in the rateof dyeing. Accordingly, it is usually desirable to-rnaiutainthe amountof dispersing agent in the :dyebath at a minimum value, .commensuratewith the. particular dye. stuff and dyeing conditions. dispersing agentshaving a substantivity for the: fiber may be employed-to aid the actionof the dyeing ,assistant.

Thus, the-condensation product of 'diethanolamine and capric acid, whichpossesses some dispersing propertiesand detergent action, maybe used toaid in the dispersing of tributyl phosphate or pine oil, for example;

When the amount of dispersing agentis too small the. material may beunevenly dyed.; For. ,example,,the dyed fabric may exhibit round, more.heavily dyed spots when 1 the assistant employed is not,self-dispersible in. water and insufficient dispersing agent ispresent." .Accordingly,,

when such an assistant isused suflicientdispersing agent:v should bepresent toinsureeven. dyeing under the par:

ticular dyeing conditionscmployed. ,Thus,in many cases.

a higher ratio of dispersing agentfto assistant, e.g. up

o bo t 1:= ,fsho 1 1 be used 'whena mereaqu entrate It is the usualprac-. tice in thedyeing. .of ordinary acetone-soluble cellulose acetateto incorporate into the dyebath additional amounts On the other hand,certain 5 dyebath is employed, as in a jig-dyeing, than when arelatively dilute dyebath is employed, as in winch dyeing. If desired,fabric showing the spots mentioned above may be treated to remove thespots by scouring the fabric thoroughly at a high temperature, e.g. 95C., in the presence of a strongemulsifying agent, such as the nonionicreaction product of castor oil and ethylene oxide sold under the nameEmulphor ELA719; the scoured spot-free fabric may then be redyed.

The dyeing assistant may be added directly to the aqueous dyebathtogether wiht the dyestuif, or it may be applied to the surfaces of thetextile material before said textile materialis brought into contactwith the dyebath. In the latter case, the process of this invention isadvantageously carried out by padding a dispersion of the dyeingassistant, e.g. an aqueous emulsion containing the assistant and'adispersing agent, onto the surfaces of a fabric comprising fibers of thecellulose acetate of very high acetyl value, and then introducing theresulting wet fabric into the dyebath.

In the practice of this invention, the aqueous dyebath is maintained atan elevated temperature, best results being obtained at temperatures ofat least about 65 C. Tempeartures up to the boiling'point of the dyebathmay be employed, and, in fact, the dyebath may be maintained undersuperatmospheric pressure in order that it may be heated to temperatureswell above the normal boiling point of said dyebath, but this has notbeen found to be necessary from a practical standpoint.

The amount of assistant, the pH of the dyebath, the proportion ofdyestuif in the dyebath, and the liquor ratio, i.e. the ratio of theweight of the dyebath to the weight of the fabric, may be varied widely.Thus, ex cellent results have been obtained when the amount of assistantin the dyebath has been varied from about 5 to 20% (based on the weightof the fabric)-ar1d-when the pH of the dyebath has varied from about 6to 9. It is preferred, of'course, to employ dyebaths containing minimumamounts of the assistant. With respect to the amount of the dyestuff,this is of the same order as that generally employed in dyebathscontaining dispersed cellulose acetate dyestuffs, e.g. about :1 to 4.0%(based on the weight-of the fabric). For best resultsthe liquor ratioshould not be too high, e.g. it should not be above about 80, preferablyabout 50 or less, e.g. about 50 to 30 when the dyeing is carried out ina winch, since at higher liquor ratios the dyebath is generally toodilute. When methods other than winch dyeing. are used for bringing the"dyebath into contact withthe material to be dyed, the liquor ratio isappreciably lower,.e.g. about 10 in the case of package dyeing and aboutin the case of jig dyeing;

When the assistant is applied to the textile material before the textilematerial is brought into contact with the dyebath, the total amount ofdyeing assistant used may be reduced substantially, particularly in thecase of those dyeing assistants, such as, for example, tripropylphosphate, tributyl phosphate, dimethyl phthalate and dibutylphthalate,.which are not removed readily from the surfaces of thetextile material by the dyebath. Thus, an emulsion having aconcentration of about 1 to 5% of dyeing assistant may be applied to thefabric in an amount about equal to the weight of the fabric (e.g. about75 to 100% of emulsion based on the weight of the fabric) at atemperature of, say, 20 to 60 C., before the fabric is introduced into adyebath containing no added dyeing assistant. Though the total amount ofdyeing assistant used is then only about 1 to 5%, based on the weight ofthe fabric, the results are equal to or better than those obtained usinglarger amounts, e.g. 5 to 20% of assistant, in the dyebath. In fact,when this method is used instead of the method in which the assistant isadded directly to the dyebath, the rate of dyeing is generally higher sothat the dyeing period is shortened considerably. With those assistantswhich are more easily removed from the surface of the fabric by theaction of the dyebath, such as the condensation product ofdiethanolamine and capric acid, it is preferable to use dispersionscontaining a higher concentration of the assistant, e.g. about 5 to 10%,when the dispersions are applied to the fabric before the latter isbrought into contact with the dyebath.

After the textile material made of cellulose triacetate or othercellulose acetate of very high acetyl value has been dyed, it is rinsed,in the manner well known in-the dyeing art, to remove dyebath componentsother than the dyestuff andis then subjected to a heat treatment inaccordance with this invention. The heat treatment has the effect ofimproving the wash fastness, perspiration fastness, and other propertiesof the textile material, e.g. safe ironing temperature, ability to takepermanent pleats, glazing resistance, and moist steam pressingshrinkage.

The temperature'at which the heat treatment is carried out and theperiod of treatment depend to some extent on the heat treating medium.Thus, when hot air is employed as a heating medium, an improvement inthe properties of the textile material may be obtained by the use oftemperatures of about C., thoughoptimum results are obtained atconsiderably higher temperatures, e.g. at temperatures of about 250 C.Thus, heat treatment of a dyed staple fiber, yarn or woven fabric ofcellulose triacetate in hot air at a temperature of 190 C. for 20minutes effects a considerable improvement in the wash 'fastness of thematerial and the safe ironing temperature of the fabric, but only arelatively minor improvement in the resistance to glazing and resistanceto shrinkage on moist steam pressing, while heat treatment of the samefabric in hot air at a temperature of 250 C. for several seconds resultsin a very marked improvement in all of these properties. Furthermore, aswill be evident'from the results described in the preceding sentence,the desired improvement in the properties of the textile material may beobtained much more quickly when {the higher temperatures are employed.For best results, the heat treatment should not be carried out at suchtemperatures and for such long periods of time as to materially impairthe color, tensile strength and elongation at break, or other mechanicalproperties, of the textile material.

The heat treatment is a dynamic process and involves the heating up ofthe textile material to the elevated temperature. Actually, it isthought that the textile material need beat this elevated temperaturefor only a very short time and that most of the time is consumed inheating the fabric to this temperature. However, the use of heat sourceshaving very high temperatures in order to shorten the-time of treatmentis not altogether practical since the outer surface of the fiber orfabric may then reach a temperature sufficiently high to cause damagebefore the interior of the fiber or fabric has reached the propertemperature. In addition it is very difficult to measure the exacttemperatures actually attained by the fabric during heat treatment.

It will be therefore apparent that for commercial heat treatment of anyparticular fabric and with any particular apparatus it is best-to makesome simple trials in order to determine the best conditions for heattreatment. Such trials are carried out easily and quickly by exposingsamples of the fabric to heat in the apparatus to be used, employingvarious conditions of time and temperature and by observing thecharacteristics of the treated samples, such as safe ironing point andextent of degradation, if any.

The textile material may be heat-treated in the relaxed condition orwhile it is held under tension. The heattreatment may be carried outwhile the dimensions of the textile material are maintainedsubstantially constant, as

by the use of a frame or tenter. Heat-treatment in the relaxed conditionresults in some shrinkage of the textile material. This shrinkage isvery small in the case of cellulose acetates having acetyl values above61% Thus, when a yarn of cellulose acetate having an acetyl value of61.3% is heated in a relaxed condition to a tempera-v ture of 250 C. for30 seconds and then cooled, the yarn shrinks only about 4%. Theshrinkage is normally less when woven fabric, rather than yarn, isheat-treated.

The heat treatment in the relaxed condition, with ac-. companyingshrinkage, is often desirable when it is necessary to avoid removal ofthe crimp in the fibers making up. the textile material and to avoidflattening of the fabric. The optimum times for heat treatment willdepend to some extent on the weight and construction of the fabric,since, for example, a longer period of time will be required to bringthe fabric to the desired elevated temperature in the case of a heavier,or more tightly woven fabric than in the case of a lighter or moreloosely woven fabric.

Thus a relatively light woven fabric having a weight of about 4 ouncesper square yard, described more fully below, is advantageously heated inhot air at a temperature of about 230 C. for at leastabout 5 seconds,butnot above about 1 minute in order to avoid damaging the fabric,preferably for slightly less than 1 minute. For the same fabric attemperatures of 250 C. and 270 C., the corresponding times are at leastabout 5 seconds and at least about 2 seconds, respectively, and notabove about 30 seconds and not above about seconds, respectively.

When a relatively heavy fabric, having a weight of about 6% to 7 ouncesper square yard and made up of staple; fibers, described more fullybelow, is employed, the corre- I cellulose acetate having an acetylvalue of 61.3%, the. shrinkage'on repeated moist steam pressing can bere-:

duced to less than 4% and the tendency for the fabric to glaze onpressing and ironing can be practically eliminated.

The relatively light fabric referred to above is composed of yarns of150 denier, each yarn beingmadeup of- 40 continuous filaments ofcellulose triacetate.v The fabric When maximum improvement in theresistance is of 2 over 1 twill construction and has 120 ends and 72picks per inch.

The relatively heavy fabric referred to above is composed of staple 3denier 2 inch long fibers, spun to 20 S 2-ply yarn (cotton count) with atwist of 15 Z in the.

singles and 14 S in the ply, and woven 44 ends and 42 picks per inch ina tropical suiting construction.

When saturated steam is used as the heating medium the heat treatmentmaybe effected at lower temperatures.

Thus a significant improvement in the properties of the fabric may beobtained by treating the fabric with saturated steam at a pressure of'20 pounds per square inch gauge for a period of five minutes, althougha treating periodof 30 minutes gives best results at this pressure.

Steam at higher pressures, e.g. 30 to 50 pounds per square inch gauge,may also be employed. When treating with steam it is desirable toprevent any droplets of condensate from coming in contact with thematerial being treated since such droplets sometimes cause spotting ofthe dyed material.

If desired, other heat treating media may be employed, 1

e.g. superheated steam, hot oil or molten metal,or the textile materialmay be heated by subjecting it to a high frequency electric field or toinfrared radiation, or the textile material may be heated by contactwith hot rolls or hot platens. The heat' treatment may be carried out atatmospheric, superatmospheric or even subatmospheric pressure.

Heat treatment tendsto cause the fabric. to stilfen slightly. Thisstiffness may. be eliminated by subjecting the.

fabriclto mechanical working, e.g. to the operations known as-button-breaking or cold calendering or to wet processing, e.g. washingor decatizing. The tendency to stiff-' ening may also be overcome by theapplication of avery finely divided solid material to the textilematerial before heat treatment; for example, a dispersion of silica,such as those .anionic dispersions of one micron particles of silicaknowmas Ludox or'Syton W-20 or-DS, may be about 180 C. On heat treatingsuch fabrics in accordance with this invention the safe ironingtemperature is raised by more than about 20 C., to a value of aboveabout220. C. or 230 C., usually above about 240 C3 The effect of theheat. treatment is most pro-.

nounced in. the case of those cellulose acetates hav ing the highestacetyl values. Thus, for example, cellulose acetates. having acetylvalues ofabout 61% or 62% or higher, calculated as combined acetic acid,show greater improvements, on heat-treatment, in resistance to glazing,resistance :iO moist stearn pressing shrinkage and in ,safe ironingtemperature as compared with'cellulose acetate of acetyl values of59.5%, calculated as combined acetic acid.

heat-treatment of this invention the fabric is damaged severely. Foroptimum properties for fabrics sold on a commercial scale, the acetylvalue should be at least 60% and preferably at least 61 In accordancewith one aspect'of this invention, the,

heat treatment may 'be' applied to dyedtextile materials in which themajor portion of the dye has been absorbed only on the surface of thefibers. Thus, when certain dyeing assistants, e.g. polybasic acid esterssuch as tributyl phosphate, dimethyl phthalate and diethyl phthal- .ateare employed, it is observed that even at tempera- I tures as low as 65C. there is an initial strike of the dye onto, the fiber to produce ..aperipherally dyed, or surface dy material during the ,early stages ofdye! ing. The fiber is truly' dyed as' shown by the fact thatexamination of fiber cross-sections: reveals that the dye is withinthefiber, and the fact that the dye is not removed by rinsing... Whenthis material is subjected to a heat treatment in accordance with thisinvention, the dyed material becomes highly fast to washing and does notcrock due in part to further diffusion of dyestutf into the fiber crosssection."

Heat-treatment in accordance with this; invention has" the additionaleffect of removing a large part of the dyeing assist-ant from thetextile material. .Sincethe'dyeing assistants are substantive to thecellulose acetate of very high acetyl value, an appreciable proportionof these assistants remainsv in the textile material after the dyeingoperation, even after the. textile .materiaL is rinsed or scoured. Forexample, two portions of a fabric of cel lulose acetate having an acetylvalue of 61.3%, which portions had been dyed, one 'in the presence oftributyl phosphate as the assistant and the other in the presence oftripropyl phosphate, were found, after scouring at 'F., tohave P0contents, resulting'from the presenceof the above phosphates, of 1.64%and 1.44%, respectively.

After the portions of fabric had been heated for 31 sec: onds bysubjecting them to infra-red radiation so that their surfaces attained atemperature of about 245 255 C., their P0 contents were reduced to 0.12%'and 0.08%

In contrast, when a fabric of ordinary cellulose acetate, e.g. of 54.5%acetyl value, is subjected to, .the.

respectively, due to vaporization of the phosphates. Similar results areobtatined with other assistants volatile at the temperatures of heattreatment, e.g. pine oil. However, the high temperature slow dyeingcellulose acetate dyestuffs employed in this invention do not volatilizeor decompose to any appreciable extent during the heat treatment andremain substantially entirely in the textile material.

In some cases it is advantageous to scour the textile material after theheat treatment. Such scouring has been found to reduce any tendency thematerial may have to stain the water used for the first homeorlaundry-washing thereof, presumably by the removal of a very smallamount of loosely adherent dyestuff. This scouring treatment may becarried out, for example, at a temperature of 120 to 150 F. using anaqueous scouring bath containing 0.5 to 2 grams per liter of a nonionicor anionic detergent such as Emulphor ELA-- 719 or Duponol RA.

Any of the usual finishing agents may be applied to textile materialsproduced in accordance with this invention. For example, there may beapplied to the textile material a silicone finish composed of apolysiloxane containing methyl or other hydrocarbon groups, andpreferably also hydrogen atoms, directly attached to the silicon atoms.Other finishing agents which may be applied include Waxy polyethylene;waxy sulfonated fatty materials; waxy cationic long chain aminecompounds; finelydivided silica; finely divided titanium dioxide; andresinous or resin-forming condensation products such as the reactionproducts of melamine, stearamide and formaldehyde. Other resinous orresin-forming condensation products which may be applied include thereaction products of formaldehyde with urea or thiourea or substitutedand cyclic vureas such as ethylene urea, or melamine, alkylationproducts of such reaction products, e.g. dimethoxymethyl urea,trimethoxymethyl melamine or N,N-dimethoxyme.thyl ethylene urea. Theamount of finishing agent applied is relatively small, e.g. about /4 to2%, and the finishing agent is most conveniently used by applying to:the textile material an aqueous dispersion of said finishing agent,following which the textile material is dried and, .when it .isnecessary to cure said finishing agent as in thecase of silicones orresinous condensation products, then baked atan elevated temperature.Suitable finishing agents are sold under the names Decetex 102, Decetex104, Decetex 108, Hydroprof, Repelletex P 30, Ahco 111, Ahcovel A,"Ahcovel E,'Ahco-vel:G, Ahcovel NC, Ahcovel R, Aquex 16, Aquex 16x,Permel, Aerotex Softener H, Parop'on R, General Electrics Silicone81386, Syton W-20, Dullatone, Aerotex Resin 801, Aerotex Cream 450,Rhonite R1,--and Rhonite N5.' The finishing agents may be applied to thedyed material before but preferably after the heat-treating operation.However, certain finishing agents, such as the silicones, e.g. Decetex104, may be applied to the textile material and cured even before thedyeing without appreciably affecting the rate of dyeing. Those finishingagents which act as surface lubricants, e.g. the silicones, the waxypolyethylenes and other waxy softeners, and the condensation products ofmelamine, formaldehyde and stearamide, increase greatly the resistanceof the dyed textile material to abrasion, which abrasion sometimescauses fragments of fibers to break off and thus gives the appearance ofcrocking. Such finishing agents also improve the tear strength of thematerial. Combinations of finishing agents may be employed, e.g.combinations of silicones or waxy polyethylenes with urea-formaldehydeor melamine-formaldehyde condensation products, or combinations ofdispersed finely divided silica and silicones, together, if desired,with ureaor melamine-formaldehyde condensation products.

Cellulose acetate of very high acetyl value colored with certaindispersed cellulose acetate dyestuffs shows a tendency to fade onexposure to acid fumes, such as combustion gases and, in some cases onexposure to ozone. To reduce this tendency'it is often desirable toapply a suitable inhibitor to the textile material. The inhibitor may beapplied, for example, by including it in the dyebath, by padding on asolution or dispersion of the inhibitor before or after dyeing, or byapplying the inhibitor after the heat-treatment. It is generallydesirable to apply the inhibitor before the heat-treatment. Examples ofsuitable inhibitors are those conventionally employed for ordinaryacetone-soluble ceilulose acetate, such as diphenylimidazolidine,N,N-diphenylethylenediamine, N,N dibenzylethylenediamine and methyl orother alkyl substitution products thereof, diphenylbenzamidine,diphenylacetamidine, benzylethylaniline, sodium formate or Meleine(melamine which has been partly solubilized in water by reaction with asmall amount of formaldehyde). For prevention of fading by ozone,antioxidants, e.g. tertiary butyl hydroquinone, alkylated phenols suchas Ionel and Inhibitor 162, and many of the aforementioned nitrogenousinhibitors, maybe employed. The amount of inhibitor is generally small,e.g. 0.5 to 3% based on the weight of the textile material.

It is found that, even without the use of an inhibitor, dyed textilematerial of cellulose acetate of very high acetyl value which has beenheat-treated in accordance with this invention shows a much smallertendency to fade on exposure to ozone than the same dyed fabric beforeheat-treatment.

As stated, heat-treated fabrics of this invention are capable of beingpermanently pleated. Thus, in one example, a heat-treated fabric ofcellulose acetate having an acetyl value of 61.3% is accordion-pleatedon a steam press using 500 pounds head pressure while steaming for 10seconds with steam having a pressure of 50 pounds per square inch gauge;the pleats are retained on washing. Permanent pleats may also beobtainedby pleating the fabric before or during the heat-treatment; forexample, a fabric which has not been heat-treated may be pleated betweenmetal rolls having a temperature of 350 F. and then furtherheat-treated, e.g. with steam at a pressure of 20 pounds per square inchgauge in an autoclave.

If desired, the cellulose acetate textile material of very high acetylvalue may also be embossed with any suitable pattern before, during or.after heat treatment. For example, a woven fabric of cellulose acetateof very high acetyl value which has not been heat-treated may be given asurface-pattern which is fast to Washing'by the application of a metalembossing roller having a temperature of 400 F.

While the process of this invention has been described particularly inconnection with textile materials composed entirely of fibers ofcellulose acetate of very high acetyl value, it is also applicable toother textile materials comprising such fibers, e.g. to materials madeup of blends of such fibers and other fibrous materials, such as wool,cotton, rayon, glass fibers and asbestos. Such blends may be dyed undersuch conditions that all types of fibers in the blend are colored at thesame time or they may be dyed in stages so as to color the differenttypes of fibers successively. The blends of fibers may be cross-dyed orunion-dyed. The process of this invention is applicable to textilematerials made up of staple fibers of cellulose acetate of very highacetyl value as well as those made up of continuous filaments of saidcellulose acetate.

Although the heat treatment of this invention is of greatest value andyields optimum results when used on cellulose acetate textile materialsof very high acetyl value dyed with cellulose acetate dyestuffs of thehigh temperature slow dyeing type, it may also be applied to such highacetyl value cellulose acetate textile materials dyed with otherdyestuffs, e.g. with low temperature or medium temperature types ofdispersed cellulose acetate dyestuffs such as 2-nitro 4-sulfonamidodiphenylamine, p-nitrophenyl azo diethyl aniline or l-amino 4-hydroxyanthraquinone. In such cases the safe ironing temperature, resistance.to glazing, resistance to shrinkage on moist steam pressing and abilityto take permanent pleats are improved, as is the wash fastness of thematerial, but there is not a suflicient improvement in the latterproperty to enable the material to pass the #3 A.A.T.C.'C. wash fastnesstest. Furthermore, the materials dyed with dyes of the high temperatureslow dyeing type generally possess superior resistance to gas fading,light fading and sublimation.

Afterthe heat treatment of this invention the cellulose acetate textilematerials of high acetyl value are much more resistant to dyeing thanthe same materials before However, the rate at which the.

the heat treatment. heat-treated materials take up the dye may bemarkedly increased by the use of the dyeing assistants previouslydescribed and by the use of higher dyebath temperatures, e.g.temperatures of 95 to 100 C. and higher.

The following examples are given to illustrate the in vention further.

Example I ethanol into an evaporative atmosphere, is dyed in ac- Thefabric used is of 2' cordance with this invention. over 1 twillconstructionweighing about 4 ounces per square yard and having 120 endsper inch and 72 picks per inch, each yarn in both weft and warp having adenier of 150 and being composed of 40 continuous filaments. The dyeingoperation is carried out for one hour in an aqueous dyebath maintainedat a temperature of 85 C. and containing 2% (based on the weight of thefabric) of the dyestuif Eastman Blue GLF (containing about 40% activedye material consisting of 1,8- dihydroxy 4 (para beta-hydroxyethyl)anilido-S-nitro anthraquinone), (based on the weight of the fabric) oftri-n-propyl phosphate, and 21% (based on the weight of the fabric) ofIgepon T Ge a dispersing agent which comprises as its active ingredient16% of the sodium salt of oleyl taurate. The liquor ratio, ie the ratioof the Weight of the dyebath to the weight of the fabric, is 50. Afterthe dyeing operation the wet fabric is rinsed for minutes at 35 C. in abath containing 2 grams per liter of soap, and dried.

Four other portions of'the same fabric are dyed. 1 The conditionsof'dyeing, which are different in each'case, are identical with thedyeing conditions, given in paragraph (a) above with the followingexceptions:

(b) There is substituted for the tripropyl phosphate an equal weight ofpine oil. I

(c) There is substituted for the 10% of tripropyl phosphate, 10% (basedon the weight of the fabric) of Alrosol C, a condensation productproduced by heating two moles of diethanolamine with one mole of capricacid while splitting out-the water of reaction, said condensationproduct comprising N,N-dihydroxyethyl capramide. This condensationproduct is a liquid soluble in water and in organic solvents; its watersolutions are clear, thin and slightly alkaline, do not gel on dilutionwith water and tolerate electrolytes.

(d) The dyebath contains no added assistant or Igepon T, but merely theEastman Blue GLF and water.

(e) The dyebath contains no added assistant, but merely the EastrnanBlue GLF, water and. 1% (based on the weight of the fabric) of theIgepon T The following table compares the results obtained in the abovedyeings:

Type of dyebath:

(a) Tripropyl phosphate,

Color of fabric Igepon T i Deep blue shade. (b) Pine oil, Igepon T andwater Shade almost asdeep as (a).

(c) Alrosol C and Water Shade somewhat lighter than (b).

(d) Water Very pale shade;

much lighter than (c).=

(e) Ig'epon T and water Paler than (d).

Example II The procedure of Example 1(a), .(b), (c), (d) :and

(e) is repeated except that the dyestutf Celliton Blue,

AF (containing about 40% of active dye material) is substituted forthe.Eastman Blue GLF. are tabulated below:

Type a of dyebath:

(a) Tripropyl phosphate,

'Igepon T and water (b) Pine oil, Igepon T. and

water Color of fabric Deep blue shade.

(e) Igepon T and water Shade about the same as-(d).

Example ;III.

(a) Awoven fabric composedof'fibers of cellulose acetate having anacetylv value. of 62.0 to 62.5%, calcu lated as combined acetic .acid,said fibers having been produced by spinning a solution-of saidcellulose acetate in an organic solvent therefor into an'eva-porative'atmosphere, is dyed for-one hour in an aqueous dyebath maintained at atemperature of C. and containing 1% (based on the Weight of the fabric)of .the dyestutf" Eastone .Red GLF, comprising4-nitr-o-2-methylsulfonephenyl azo 4'(N-beta-hydroxyethyl-N-difluoroethyl) aminobenzene, 10% (based on theweight of the fabric) of pine oil, and 1% (based on the weight of thefabric) of a dispersing agent comprising equal proportions, by

weight, of ;the dispersing agents known as Emulphor ELA-'719 (aHOD-.iOIllCt product of the reaction of castor oil and ethylene oxide)and .Qu'adronate? (a mahogany soap, ie a sodium petroleum sulfonate, oflow molecular weight).- The liquor ratio is 50 and the fabric iswashedafter the dyeing operation in a manner similar.-

to Example I, and dried.

The otherportions of the same .fabricI are dyed. The

dyeing procedures, which are different for each of said' portions, areidentical with those set out in the preceding paragraph, with thefollowing exceptions:

(b) There is substitutedvfor the:10% of pine oil 10% (based-on theweight of the fabric) of Alrosol C and the dispersing agent is omitted.I

(c) The pine oil and dispersing agent are omitted.

The results are tabulated below:

Type of dyebath:

(a) Pine oil, dispersing agent' Color .of fabric and water Deep redshade. (b) Alrosol C and water:.'. Somewhat lighter than (a).: (0) WaterPale red shade, much lighter than (b).

The results Example IV The dyed fabrics of the preceding examples (I, IIand III) are heat treated in an oven in circulating hot air having atemperature of 230 C. for 60 seconds while said fabrics are held inframes to maintain their dimensions substantially constant throught theheat treatment. The heat treated fabrics are subjected to the A.A.T.C.C.#3 wash fastness test and are found to retain their color, withoutappreciable change of color or staining, even after 3 repetitions ofsaid test. The heat treatment raises the safe ironing temperature of thedyed fabric by 60 C., i.e. from 180 C. to240 C., improves the glazingresistance of the fabric, and reduces the degree of wrinklingwhich-occurs during laundering. The heat treated fabric shrinks9% inarea after 12 pressings in moist steam, as compared with a 15% shrinkagefor fabric which has not been heat-treated. The heat-treated fabric maybe pleated in a steam press using a damp cloth and high mechanical presspressure, and the resulting pleats are permanent to repeated washingat160 F. The hand and strength of the fabric is substantially the samebefore and after the heat treatment.

The safe ironing temperature, referred to above, is determined by theuse of a standard hand iron having a weight of five pounds and an areaof its sole plate of 22 /2 square inches. The test is conducted byheating the iron until a selected 2-inch-square area of the sole plateadjacent the tip of the iron has the desired temperature. A 2-inchsquare of the fabric to be tested is placed on an ironing surfacecomprising a flat board covered with one inch of sponge rubber, overwhich are 4 layers ofcottonflannel, and the iron is then placed on thefabric so that the aforesaid selected area of the sole plate coincideswith the fabric. The placing of the iron is carried out by hand withoutany lateral motion of the iron on the fabric and without any applicationof hand pressure to the iron on the fabric. After the iron has rested onthe fabric for exactly 10 seconds, the iron is lifted straight up offthe fabric. The test is repeated with the iron heated in 10 C.increments for each test until there is evidence of damage to thefabric, e.g. until the fabric sticks to the iron, becomes boardy orchanges in color. The maximum safe ironing temperature is thattemperature which is 10 C. below the temperature at which the first signof damage to the fabric occurs.

Example V The procedure of Example 1(a) is followed except thattri-n-butyl phosphate in the amount of 5% (based on the weight of thefabric) is used in place of the tripropyl phosphate; the dispersingagent is a mixture of 41% (based on the weight of the fabric) ofEmulphor ELA-7l9 and 4% (based on the weight of the fabric) ofQuadronate; the dyestuif is Amacel Rubine IX and is used in the amountof 2% based on the weight of the fabric; and the dyeing is carried outat 80 C. The fabric is dyed a full red shade.

Example VI A portion of the woven fabric described in Example I is dyedfor 30 minutes in an aqueous dyebath maintained at a temperature of 65C. and containing 2% (based on the weight of the fabric) of thedyestuft' Celliton Blue AF (containing 40% active dye material), 10%(based on the weight of the fabric) of tri-n-butyl phosphate, and 0.5%(based on the weight of the fabric) of Quadronate and 0.5% (based on theweight of the fabric) of Emul-phor ELA-719. The tributyl phosphate,which is a liquid, is first mixed with the Emulphor ELA 719 andQuadronate and the resulting paste is then mixed with the water of thedyebath. The liquor ratio is 50. After the dyeing operation the Wetsurface dyed fabric is rinsed for minutes at 35 C. in a bath containing1 gram per liter of Igepon T Gel. The

14 fabric is dyed a deep blue shade. When this material is subjected toa heat treatment in accordance with this invention, it becomes highlyfast to washing and does not crock.

Example VII A portion of the woven fabric described in Example I ispadded at a temperature of 50 C. with a bath comprising an emulsioncontaining 5% by weight of tri-nbutyl phosphate, /2 of Emulphor ETA-719,/2% of Quadronate and the remainder water, all of said proportions beingbased on the .total weight of the emulsion. Afterthe fabric has been incontact with the padding bath for 30 seconds, the fabric, carrying 100%of its weight of said emulsion, is introduced into, and maintained for/2 hour at C. in, a dyebath containing 2% (based on the weight of thefabric) of Cellition Blue AF, the liquor ratio being 50. The fabric isdyed a full blue shade.

Example VIII Example I is repeated except that the fabric is composed offibers of cellulose acetate having an acetyl value of 59.5%, calculatedas acetic acid. Substantially thesame results are obtained as in ExampleI.

The dyed fabric is subjected to the heat treatment described in ExampleIV for a period of 30 seconds. Substantially the same results as inExample IV withrespect to-wash fastness are obtained. The safe ironingtemperature is raised and the pleating characteristics, resistance towrinkling and mussing during laundering, and resistance to pressingshrinkage in moist steam are improved, but not nearly to as great anextent as in the case of Example IV.

Example IX 50 kilograms of woven fabric of cellulose acetate of 61.3%acetyl value are placed on a jig, scoured, and dyed on the jig at aliquor ratio of 4:1 with an aqueous mixture comprising 3000 grams ofCelliton Blue AP, 390 grams of Eastone Red GLF, 420 grams of AmacelYellow CW, 950 grams of diphenylimidazolidine, 50 grams of Igepon T Gel,grams of tetrasodium pyrophosphate and 2500 grams of a mixture of 400parts by weight of tripropyl phosphate, 400 parts by weight of the pineoil sold under the name Yarmor 350 (a mixture of hydrocarbons andalcohols, distilling in the range of 220 C., with about 50% distillingat about 200 C., at atmospheric pressure) and 100 parts by weight ofEmulphor ELA719. The dyeing is started at '85' C. and after 2 hours thetemperature of the dyebath is raised to 95 C. Total dyeing time is 6hours, during Which time the fabric is passed from one roll of the jig,through the dyebath and rolled onto the other roll of the jig and thenpassed through the dyebath to the first roll, this operation beingrepeated several times during the dyeing period, in the conventionalmanner. Thereafter the fabric is scoured and washed on the jig. Thefabric, dyed a heavy navy blue shade, is heat treated in a radiantheating apparatus for 30 seconds, during which time the fabric attains atemperature vof 230 C., and then subject to the A.A.T.C.C. #3 washfastness test, during which there is no appreciable change in shade,

Example X A fabric composed of a blend of 50% of staple fibers ofcellulose acetate of 62.5% acetyl value and 50% of viscose rayon staplefibers is dyed, at a liquor ratio of 50:1, with an aqueous bathcomprising 1% Eastman Blue GLF, 2% Eastone Red GLF, 0.75% InterchemicalAcetate Yellow HDLF40," 0.21% Resofix Blue GLN, 0.45% Cuprofix Yellow GLand 2.5% Resofix Rubine BLN, the latter three being direct dyes forcellulose, all proportions being based on the weight of the fabric. Thedyebath also contains 10%, based in portions during the dyeing. Thetemperature of dye- I ing is 90 C. The fabric is dyed in a uniformmedium brown shade. It is rinsed, then heat set by exposing it 10%,based to radiant heat for 30 seconds, during which time the fabricattains a temperature of 220 C., and thereafter padded with an aqueousmixture in such a manner as to deposit on the fabric 0.5% by Weight ofDecetex 104, 0.5% by weight of Decetex'108 (both Deceters' compositionsbeing silicone finishing agents), 10% by weight of a low condensationproduct of 1.3 moles of formalde-v hyde and 1 mole of urea, 1% by weightof Catalyst G-8 (an acidic mixture of formaldehyde and an aminehydrochloride curing catalyst for. the urea-formaldehyde product) and 2%by Weight of Cuprofix 47 (a fixative agent for direct dyes oncellulose), all'proportions being based on the Weight of the fabric.After drying the fabric is heated at 155 C. for 8 minutes to cure thefinish and then scoured.

Example. X l

100 parts by weight of a fabric of cellulose acetate of 62.5% acetylvalue are immersed and agitated for one hour in a bath having atemperature of 85 C. and comprising 4000 parts by Weightof water, 2parts by weight of the dystutf Celliton Blue Green BA, containing about40% by weight of active dye material and the balance dispersing agent,and parts by weight .of tri-n-butyl phosphate. The fabric is then rinsedin water and dried.

The resulting dyed fabric is analyzed to determine its content oftri-n-butyl phosphate and dye, and the dyebath is analyzed to determinethe concentration of trin-butyl phosphate therein.

For comparison, the dyeing is repeated under identical conditions exceptthat in one instance the phosphate is entirely omitted from the dyebathand,,in the other cases, an equal amount of tri-n-ethyl or tri-n-propylphosphate is employed in place of the tributyl phosphate.

The results are tabulated below:

Trialkyl phosphate concentration in dyebath after 1 hour of dyeing,percent Trialkyl phosphate content of dyed Iabric, percent Dye contentof dye fabric, percent 'Irialkyl phosphate \MNN commie Tributyl 1 Basedon weight of the dyed fabric. 2 Based on the weight of the dyebath.

Example XII before padding, of Celliton Blue Green BA, at: a.

liquor ratioof 40. The fabric is then rinsed and dried.

The. resulting dyed fabric is analyzed to determine its.

content of tri-n-butyl phosphate and dye.

For comparison, the procedure described above is re peated, using nophosphate in the padding bath, or using tri-n-ethyl phosphate ortri-n-propyl phosphate in place 1 5 of the tri-n-butyl phosphate,..allother conditions being identical. The results are tabulated below:

Dye content of Trialkyl phosphate fabric, percent 1 Based on the weightof the dyed fabric.

Example XIII 100 parts by Weightof a textile fabric of celluloseacetateof 61.3% acetyl value are immersed: and agi: tated in a dyebathcontaining;5000 parts by Weight ofwater, 3 parts by weight of CellitonFastBlueaAF, 12.5 parts by weight of diethyl phthalate and 2.5 parts byweight of Tween a polyoxyethylene sorbitan trioleate). The dyeing isstarted with the dyebath at a; temperature of 60 C-., which is raised toC. as the dyeing progresses. .The fabric is dyed in a full, very levelblue shade.

Example XIV Other examples of mixtures of dyeing assistants anddispersing agentsxsuitable for use with the aforementioned celluloseacetate dyes of the high temperature slow dye--. ing type are:

4 parts by Wei ght of tn'butyl phosphate 3 4 parts by weightof Yarmor 350- 1 part by weight of Emulp'hor-ELA -7l9 V 3 parts by weight oftributyl phosphate 3 parts by weight of tripropyl phosphate 1 part byweight of Emulphor ELA719' I 3 parts by weight of tributyl phosphate 2parts by weight of Yarmor 35 0 2 parts by Weight of Alrosol C 1 part byweight of -Emulphor ELA719" 4 parts by weight of diethyl phthalate 4parts by weight of tripropyl phosphate 1 part by weight of -Tween 80 I 4parts by weight of phenyl ethenof ethylene glycol 4 parts by weight ofphenyl etherof diethylene glycol 0.5 part by Weight of Span 20 05 partby weightof Tween 20 It is:to be understod that the foregoing detaileddescrip'-' tion is given merely by way of illustration and thatrnany'variations may be made therein without departing fromt the spirit of ourinvention.

Having .described our invention,- what we desire secure byLetters-Patent is:

1. Process for thetreatment of textile, material, com prising dyeing atextile ,material, comprising fibers of cellulose acetate having anacetyl value of at least 59%, calculated as combined acetic. acid, withadispersed celgt lulose acetate dye of the hightemperature' slow dyea ingtype in the presencev of an asisstant for increasing the rate of. dyeingof said textile material, said assistant comprising the condensationproduct of a hydroxyalkyl-E amine and a long chain fatty acidLf r2.Process for the; treatment of textile material, com-f prising dyeing atextile; material comprising fibersv of cel.- lulose acetate having anacetylwalue .of at-least 59%,. calculated as combined acetic acid, witha dispersed cel lulose acetate dye of the .high temperature slow dyeing*1? type in the presence of an assistant for increasing the rate ofdyeing of said textile material, said assistant comprising thecondensation product of a hydroxy-lower alkylamine and a long chainfatty acid.

3. Process for the treatment of textile material, comprising dyeing atextile material comprising fibers of cellulose acetate having an acetylvalue of at least 59%, calculated as combined acetic acid, with adispersed cellulose acetate dye of the high temperature slow dyeing typein the presence of an assistant for increasing the rate of dyeing ofsaid textile material, said assistant comprising the condensationproduct of a di(hydroxy-lower alkyl)amine and a long chain fatty acid.

4. Process for the treatment of textile material, comprising dyeing atextile material comprising fibers of cellulose acetate having an acetylvalue of at least 59%, calculated as combined acetic acid, with adispersed cellulose acetate dye of the high temperature slow dyeing typein the presence of an assistant for increasing the rate of dyeing ofsaid textile material, said assistant comprising the condensationproduct of diethanolamine and a long chain fatty acid.

5. Process for the treatment of textile material, comprising dyeing atextile material comprising fibers of cellulose acetate having "anacetyl value of at least 59%, calculated as combined acetic acid, with adispersed cellulose acetate dye of the high temperature slow dyeingtype" in the presence of an assistant for increasing the rate of dyeingof said textile material, said assistant comprising the condensation oftwo moles of diethanolamine and one mole of capric acid.

6. Process for the treatment of textile material, comprising dyeing atextile material comprising fibers of cellulose acetate having an acetylvalue of at least 59%, calculated as combined acetic acid, with adispersed cellulose acetate dye of the high temperature slow dyeing typein an essentially aqueous bath in the presence of about 1 to 20% on theweight of said fibers of an assistant for increasing the rate of dyeingof said textile material, said assistant comprising the condensationproduct of a hydroxyalkylamine and a long chain fatty acid and beingapplied from water in up to about 10% concentra tion by weight.

7. Process for the treatment of textile material, comprising dyeing :atextile material comprising fibers of cellulose acetate having an acetylvalue of at least 59%, calculated as combined acetic acid, with adispersed cellulose acetate dye of the high temperature slow dyeing typein an essentially aqueous bath in the presence of about 1 to 20% on theweight of said fibers of an assistant for increasing the rate of dyeingof said textile material, said assistant comprising the condensationproduct of two moles of diethanolamine and one mole of capric acid andbeing applied from water in up to about 10% concentration by weight.

8. Process as set forth in claim 1 and including the further step ofheat treating the dyed material at a temperature ranging from about C.to 270 C. and discontinuing said heat treatment before any substantialdamage to the textile material occurs.

References Cited by the Examiner UNITED STATES PATENTS 1,970,578 8/1934Schoeller et al. 882 X 2,982,597 5/ 1961 Salvin et a1. 959 3,101,2368/1963 Salvin et al. 859

NORMAN G. TORCHIN, Primary Examiner.

I. HERBERT, Assistant Examiner.

1. PROCESS FOR THE TREATMENT OF TEXTILE MATERIAL, COMPRISING DYEING ATEXTILE MATERIAL COMPRISING FIBERS OF CELLULOSE ACETATE HAVING AN ACETYLVALUE OF AT LEAST 59%, CALCULATED AS COMBINED ACETIC ACID, WITH ADISPERSED CELLULOSE ACETATE DYE OF THE "HIGH" TEMPERATURE SLOW DYEINGTYPE" IN THE PRESENCE OF AN ASISSTANT FOR INCREASING THE RATE OF DYEINGOF SAID TEXTILE MATERIAL, SAID ASSISTANT COMPRISING THE CONDENSATIONPRODUCT OF A HYDROXYALKYLAMINE AND A LONG CHAIN FATTY ACID.